Samples of tissue, bodily fluids, etc. are frequently taken from patients for analysis to help in diagnosing disease or monitoring the progress of treatment. For example, samples of cells from the lungs or gastrointestinal tract are taken with a cytology brush. The brush is rubbed against tissue to scrape cells from the surface and collect them in the bristles. Other sampling techniques sever tissue from the body. For example, biopsies are taken with a needle device that penetrates the tissue and then severs a sample with a sharp cutting cannula. A biopsy forceps device is another example. This device is a catheter with a jaw-type cutter at its end. The catheter is threaded through an endoscope to a position deep within the body where it bites a sample of tissue from a desired location. Samples of tissue are taken from within blood vessels using an artherectomy cutter. An artherectomy cutter is a catheter that can be threaded through a blood vessel to a desired site. A cutting member is provided at the end of the catheter. The cutting member can be pressed against a desired site in the blood vessel, such as the site of a vascular occlusion resulting from the build up of plaque, and then actuated to sever occluding matter from the wall of the blood vessel. Samples of bodily fluids are typically drawn from body conduits.